Issue with boolean filterOptions

[alexggordon]

We've run into an issue with the filterOption prop. The issue is in the filterMixin.js in the filterOption function.

  filterOption(input, child, defaultFilter = defaultFilterFn) {
    if (!input) {
      return true;
    }
    const filterOption = ('filterOption' in this.props) ?
      this.props.filterOption : defaultFilter;
    if (!filterOption) {
      return true;
    } else if (child.props.disabled) {
      return false;
    } else if (typeof filterOption === 'function') {
      return filterOption.call(this, input, child);
    }
    return true;
  }

Here, if this.props.filterOption is true, then it returns true (no if/else statements handle this), however, if this.props.filterOption is false, then true is also returned (handled by the first if (!filterOption) { statement. So when you set the filterOption to true (as is the "default") it will not actually filter anything as expected.

We believe the desired behavior is when setting filterOption to true, use the defaultFilterFn, however, when setting filterOption to false, to not filter the options. Then obviously if filterOption is a function, call that function.

We've amended the filterOption function to do this with this code.

  filterOption(input, child, defaultFilter = defaultFilterFn) {
    if (!input) {
      return true;
    }

    if (typeof this.props.filterOption === 'boolean' && this.props.filterOption === false) {
      return true;
    }

    if (child.props.disabled) {
      return false;
    }

    const filterOption = typeof this.props.filterOption === 'function' ?
      this.props.filterOption : defaultFilter;

    return filterOption.call(this, input, child);
  }

However, this breaks the filterOption could be true as described in default value spec. After looking at this spec, we're not sure what it should be testing. If our assumptions above are correct, we believe this test is incorrect. Can you explain or comment on this?

[yesmeck]

Hello @alexggordon , plz see #202.